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authorRalf Baechle <ralf@linux-mips.org>2000-07-08 00:53:00 +0000
committerRalf Baechle <ralf@linux-mips.org>2000-07-08 00:53:00 +0000
commitb8553086288629b4efb77e97f5582e08bc50ad65 (patch)
tree0a19bd1c21e148f35c7a0f76baa4f7a056b966b0 /drivers/mtd/docprobe.c
parent75b6d92f2dd5112b02f4e78cf9f35f9825946ef0 (diff)
Merge with 2.4.0-test3-pre4.
Diffstat (limited to 'drivers/mtd/docprobe.c')
-rw-r--r--drivers/mtd/docprobe.c269
1 files changed, 269 insertions, 0 deletions
diff --git a/drivers/mtd/docprobe.c b/drivers/mtd/docprobe.c
new file mode 100644
index 000000000..b2c4380d3
--- /dev/null
+++ b/drivers/mtd/docprobe.c
@@ -0,0 +1,269 @@
+
+/* Linux driver for Disk-On-Chip devices */
+/* Probe routines common to all DoC devices */
+/* (c) 1999 Machine Vision Holdings, Inc. */
+/* Author: David Woodhouse <dwmw2@mvhi.com> */
+/* $Id: docprobe.c,v 1.8 2000/06/26 20:40:53 dwmw2 Exp $ */
+
+
+
+/* DOC_PASSIVE_PROBE:
+ In order to ensure that the BIOS checksum is correct at boot time, and
+ hence that the onboard BIOS extension gets executed, the DiskOnChip
+ goes into reset mode when it is read sequentially: all registers
+ return 0xff until the chip is woken up again by writing to the
+ DOCControl register.
+
+ Unfortunately, this means that the probe for the DiskOnChip is unsafe,
+ because one of the first things it does is write to where it thinks
+ the DOCControl register should be - which may well be shared memory
+ for another device. I've had machines which lock up when this is
+ attempted. Hence the possibility to do a passive probe, which will fail
+ to detect a chip in reset mode, but is at least guaranteed not to lock
+ the machine.
+
+ If you have this problem, uncomment the following line:
+#define DOC_PASSIVE_PROBE
+*/
+
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/kmod.h>
+#include <asm/errno.h>
+#include <asm/io.h>
+#include <asm/uaccess.h>
+#include <linux/miscdevice.h>
+#include <linux/pci.h>
+#include <linux/delay.h>
+#include <linux/malloc.h>
+#include <linux/sched.h>
+#include <linux/init.h>
+#include <linux/types.h>
+
+#include <linux/mtd/mtd.h>
+#include <linux/mtd/nand.h>
+#include <linux/mtd/doc2000.h>
+
+/* Where to look for the devices? */
+
+#if defined (__alpha__) || defined(__i386__)
+static unsigned long __initdata doc_locations[] = {
+ 0xc8000, 0xca000, 0xcc000, 0xce000,
+ 0xd0000, 0xd2000, 0xd4000, 0xd6000,
+ 0xd8000, 0xda000, 0xdc000, 0xde000,
+ 0xe0000, 0xe2000, 0xe4000, 0xe6000,
+ 0xe8000, 0xea000, 0xec000, 0xee000, 0 };
+#elif defined(__ppc__)
+static unsigned long __initdata doc_locations[] = {
+ 0xe4000000, 0};
+#else
+#warning Unknown architecture for DiskOnChip. No default probe locations defined
+#endif
+
+#ifdef CONFIG_MTD_DOC2000
+extern void DoC2k_init(struct mtd_info *);
+#endif
+#ifdef CONFIG_MTD_DOC2001
+extern void DoCMil_init(struct mtd_info *);
+#endif
+
+/* doccheck: Probe a given memory window to see if there's a DiskOnChip present */
+
+static inline int __init doccheck(unsigned long potential, unsigned long physadr)
+{
+ unsigned long window=potential;
+ unsigned char tmp, ChipID;
+#ifndef DOC_PASSIVE_PROBE
+ unsigned char tmp2;
+#endif
+
+ /* Routine copied from the Linux DOC driver */
+
+ /* Check for 0x55 0xAA signature at beginning of window */
+ if (ReadDOC(window, Sig1) != 0x55 || ReadDOC(window, Sig2) != 0xaa)
+ return 0;
+
+#ifndef DOC_PASSIVE_PROBE
+ /* It's not possible to cleanly detect the DiskOnChip - the
+ * bootup procedure will put the device into reset mode, and
+ * it's not possible to talk to it without actually writing
+ * to the DOCControl register. So we store the current contents
+ * of the DOCControl register's location, in case we later decide
+ * that it's not a DiskOnChip, and want to put it back how we
+ * found it.
+ */
+ tmp2 = ReadDOC(window, DOCControl);
+
+ /* Reset the DiskOnChip ASIC */
+ WriteDOC(DOC_MODE_CLR_ERR | DOC_MODE_MDWREN | DOC_MODE_RESET,
+ window, DOCControl);
+ WriteDOC(DOC_MODE_CLR_ERR | DOC_MODE_MDWREN | DOC_MODE_RESET,
+ window, DOCControl);
+
+ /* Enable the DiskOnChip ASIC */
+ WriteDOC(DOC_MODE_CLR_ERR | DOC_MODE_MDWREN | DOC_MODE_NORMAL,
+ window, DOCControl);
+ WriteDOC(DOC_MODE_CLR_ERR | DOC_MODE_MDWREN | DOC_MODE_NORMAL,
+ window, DOCControl);
+#endif /* !DOC_PASSIVE_PROBE */
+
+ ChipID = ReadDOC(window, ChipID);
+
+ switch (ChipID) {
+ case DOC_ChipID_Doc2k:
+ /* Check the TOGGLE bit in the ECC register */
+ tmp = ReadDOC(window, 2k_ECCStatus) & DOC_TOGGLE_BIT;
+ if ((ReadDOC(window, 2k_ECCStatus) & DOC_TOGGLE_BIT) != tmp)
+ return ChipID;
+ break;
+
+ case DOC_ChipID_DocMil:
+ /* Check the TOGGLE bit in the ECC register */
+ tmp = ReadDOC(window, ECCConf) & DOC_TOGGLE_BIT;
+ if ((ReadDOC(window, ECCConf) & DOC_TOGGLE_BIT) != tmp)
+ return ChipID;
+ break;
+
+ default:
+ printk(KERN_WARNING "Possible DiskOnChip with unknown ChipID %2.2X found at 0x%lx\n",
+ ChipID, physadr);
+
+#ifndef DOC_PASSIVE_PROBE
+ /* Put back the contents of the DOCControl register, in case it's not
+ * actually a DiskOnChip.
+ */
+ WriteDOC(tmp2, window, DOCControl);
+#endif
+ return 0;
+ }
+
+ printk(KERN_WARNING "DiskOnChip failed TOGGLE test, dropping.\n");
+
+#ifndef DOC_PASSIVE_PROBE
+ /* Put back the contents of the DOCControl register: it's not a DiskOnChip */
+ WriteDOC(tmp2, window, DOCControl);
+#endif
+ return 0;
+}
+
+
+static void DoC_Probe(unsigned long physadr)
+{
+ unsigned long docptr;
+ struct DiskOnChip *this;
+ struct mtd_info *mtd;
+ int ChipID;
+ char namebuf[15];
+ char *name = namebuf;
+ void (*initroutine)(struct mtd_info *) = NULL;
+ int initroutinedynamic = 0;
+
+ docptr = (unsigned long)ioremap(physadr, 0x2000);
+
+ if (!docptr)
+ return;
+
+ if ((ChipID = doccheck(docptr, physadr))) {
+
+ mtd = kmalloc(sizeof(struct DiskOnChip) + sizeof(struct mtd_info), GFP_KERNEL);
+
+ if (!mtd) {
+ printk("Cannot allocate memory for data structures. Dropping.\n");
+ iounmap((void *)docptr);
+ return;
+ }
+
+ this = (struct DiskOnChip *)(&mtd[1]);
+
+ memset((char *)mtd,0, sizeof(struct mtd_info));
+ memset((char *)this, 0, sizeof(struct DiskOnChip));
+
+ mtd->priv = this;
+ this->virtadr = docptr;
+ this->physadr = physadr;
+ this->ChipID = ChipID;
+ sprintf(namebuf, "with ChipID %2.2X", ChipID);
+
+ switch(ChipID) {
+ case DOC_ChipID_Doc2k:
+ name="2000";
+#ifdef CONFIG_MTD_DOC2000
+ initroutine = &DoC2k_init;
+#elif CONFIG_MODULES
+ initroutinedynamic=1;
+ initroutine = (void *)get_module_symbol(NULL, "DoC2k_init");
+#ifdef CONFIG_KMOD
+ if (!initroutine) {
+ request_module("doc2000");
+ initroutine = (void *)get_module_symbol("doc2000", "DoC2k_init");
+ }
+#endif /* CONFIG_KMOD */
+#endif
+ break;
+
+ case DOC_ChipID_DocMil:
+ name="Millennium";
+#ifdef CONFIG_MTD_DOC2001
+ initroutine = &DocMil_init;
+#elif CONFIG_MODULES
+ initroutinedynamic=1;
+ initroutine = (void *)get_module_symbol(NULL, "DoCMil_init");
+#ifdef CONFIG_KMOD
+ if (!initroutine) {
+ request_module("doc2001");
+ initroutine = (void *)get_module_symbol("doc2001", "DoCMil_init");
+ }
+#endif /* CONFIG_KMOD */
+#endif
+ break;
+ }
+ if (initroutine) {
+ (*initroutine)(mtd);
+#if defined(CONFIG_MODULES) && LINUX_VERSION_CODE >= 0x20400
+ if (initroutinedynamic)
+ put_module_symbol(initroutine);
+#endif
+ return;
+ }
+ printk("Cannot find driver for DiskOnChip %s at 0x%X\n", name, physadr);
+ }
+ iounmap((void *)docptr);
+}
+
+
+/****************************************************************************
+ *
+ * Module stuff
+ *
+ ****************************************************************************/
+
+#if LINUX_VERSION_CODE < 0x20300
+#ifdef MODULE
+#define init_doc init_module
+#endif
+#define __exit
+#endif
+
+int __init init_doc(void)
+{
+ int i;
+
+ printk(KERN_NOTICE "M-Systems DiskOnChip driver. (C) 1999 Machine Vision Holdings, Inc.\n");
+#ifdef PRERELEASE
+ printk(KERN_INFO "$Id: docprobe.c,v 1.8 2000/06/26 20:40:53 dwmw2 Exp $\n");
+#endif
+
+ for (i=0; doc_locations[i]; i++) {
+ DoC_Probe(doc_locations[i]);
+ }
+
+ return 0;
+
+}
+
+
+#if LINUX_VERSION_CODE > 0x20300
+module_init(init_doc);
+#endif
+